Susceptibility-resistance pattern of Neisseria meningitidis isolated in the province of Ontario, Canada.

A total of 522 N. meningitidis cultures isolated from different sources (cerebrospinal fluid, sputum, blood, naso-pharyngeal, uro-genital area, eye and rectal samples) between the years 1976-1977 in Ontario, were tested for their susceptibility pattern to 8 antibacterial drugs. Among the 522 cultures, 24.8% showed resistance to sulfadiazine (10-100 micrograns/ml) and all N. meningitidis cultures (100%) were resistant to spectinomycin (15 micrograms/ml); this feature could be used as one of the confirmation tests for N. meningitidis, especially with the strains which cause difficulty in identification and/or confirmation. Among the N. meningitidis cultures, 3.2% yielded maltose negative results in CTA sugars (cystine trypticase agar) and were also susceptible to sulfadiazine (10 micrograms/ml).